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Full-Text Articles in Physics
The Mid-Infrared Luminosity Evolution And Luminosity Function Of Quasars With Wise And Sdss, Jack Singal
The Mid-Infrared Luminosity Evolution And Luminosity Function Of Quasars With Wise And Sdss, Jack Singal
Physics Faculty Publications
We determine the 22 μm luminosity evolution and luminosity function for quasars from a data set of over 20,000 objects obtained by combining flux-limited Sloan Digital Sky Survey optical and Wide field Infrared Survey Explorer mid-infrared data. We apply methods developed in previous works to access the intrinsic population distributions non-parametrically, taking into account the truncations and correlations inherent in the data. We find that the population of quasars exhibits positive luminosity evolution with redshift in the mid-infrared, but with considerably less mid-infrared evolution than in the optical or radio bands. With the luminosity evolutions accounted for, we determine …
Hst Imaging Of The Dusty Filaments And Nucleus Swirl In Ngc4696 At The Centre Of The Centaurus Cluster, A. C. Fabian, S. A. Walker, H. R. Russell, C. Pinto, R. E. A. Canning, P. Salome, J. S. Sanders, G. B. Taylor, E. G. Zweibel, C. J. Conselice, F. Combes, C. S. Crawford, Gary J. Ferland, J. S. Gallagher Iii, N. A. Hatch, R. M. Johnstone, C. S. Reynolds
Hst Imaging Of The Dusty Filaments And Nucleus Swirl In Ngc4696 At The Centre Of The Centaurus Cluster, A. C. Fabian, S. A. Walker, H. R. Russell, C. Pinto, R. E. A. Canning, P. Salome, J. S. Sanders, G. B. Taylor, E. G. Zweibel, C. J. Conselice, F. Combes, C. S. Crawford, Gary J. Ferland, J. S. Gallagher Iii, N. A. Hatch, R. M. Johnstone, C. S. Reynolds
Physics and Astronomy Faculty Publications
Narrow-band HST imaging has resolved the detailed internal structure of the 10 kpc diameter H α+[N II] emission line nebulosity in NGC4696, the central galaxy in the nearby Centaurus cluster, showing that the dusty, molecular, filaments have a width of about 60 pc. Optical morphology and velocity measurements indicate that the filaments are dragged out by the bubbling action of the radio source as part of the active galactic nucleus feedback cycle. Using the drag force we find that the magnetic field in the filaments is in approximate pressure equipartition with the hot gas. The filamentary nature of the …
Reconciling Ag-Star Formation, The Soltan Argument, And Meier's Paradox, David Garofalo, Matthew I. Kim, Damian J. Christian, Emily Hollingworth
Reconciling Ag-Star Formation, The Soltan Argument, And Meier's Paradox, David Garofalo, Matthew I. Kim, Damian J. Christian, Emily Hollingworth
Faculty and Research Publications
We provide a theoretical context for understanding the recent work of Kalfountzou et al. showing that star formation is enhanced at lower optical luminosity in radio-loud quasars. Our proposal for coupling the assumption of collimated FRII quasar-jet-induced star formation with lower accretion optical luminosity also explains the observed jet power peak in active galaxies at higher redshift compared to the peak in accretion power, doing so in a way that predicts the existence of a family of radio-quiet active galactic nuclei associated with rapidly spinning supermassive black holes at low redshift, as mounting observations suggest. The relevance of this work …